This my third season of serious gravel riding. I'm currently riding between 100 and 150 miles a week on mix of about 60-75% gravel roads and trails in rural Hillsborough NH. One thing I've learned about riding unpaved roads, is that the rough uneven surfaces of these roads can really take a toll on your body - especially your butt and lower back. The first line of defense of course, is a proper bike fit and wider lower pressure tires. In my case, I'm riding a custom designed steel Huntsman from 44 Bikes, with 40mm Schwalbe G-One Tires at 30/35 PSI. The Huntsman was designed and built for me by Kris Henry of 44 BIkes: http://www.44bikes.com/road . Kris is a neighbor of mine, and is well aware of the demands of our local unpaved roads. I think that I can claim near optimal position, bike, and tires, for my riding. None the less, I've been finding that after few hours of gravel, my lower back and butt are pretty sore. Recently I saw some reviews of suspension seat posts, and posted a discussion here. Based on some of the comments, I decided to try the Kinekt 2.1: https://cirruscycles.com/pages/store . This is the alloy version of the post. There is a carbon version that costs $80 more and reduces the weight by about 50 gm. The Kinekt post is about 250 gm heavier than the same length standard aluminum post. To me, the 250 gm weight penalty is relatively insignificant. I've put on over 100 miles of riding on Kinekt, and I can honestly say that for me, it really reduces lower back pain and saddle discomfort. It really works. Here are the pro's and cons from my experience:Pros- Significantly reduces lower back, and saddle fatigue, discomfort, and pain.- Easy to install and set-up. Clear instructions. It does take some experimentation to find an optimal spring selection and pre-load for your riding style and conditions.- Easy to adjust spring pre-load during a ride with a simple external 4mm Allan key. Optional tool free adjusting bolt for $16, included with carbon version.- 2 Additional springs included to fine tune the spring stiffness.Cons- The spring pre-load for optimal float results in some saddle bobbing at higher cadence pedaling. This is especially noticeable on smooth pavement. While I found this bobbing a little surprising at first, I didn't notice ant loss of power or efficiency. After a few miles, I didn't notice it as a problem. Of course, you can always increase the spring load to remove the saddle bobbing, if you are riding mostly on pavement. Frankly, I wouldn't bother because even on paved roads, the float removes a lot of the buzz, which also contribute to fatigue on longer rides.- Cost -- $250 K2.1, $330 K3.1 (carbon)- Ascetics. Beauty is in the eye of the beholder -- not his backside.- Weight --- about 250 gm. Or about 1/2 filled water bottle

Recommendation: This seat post isn't for everyone. If you are comfortable with your ride after several hours of gravel grinding - don't bother. If however, like me, you find that a few hours of gravel leave your back and butt aching, then the Kinekt may be for you.

Thanks for the writeup! How does it do on washboard? I have more of an issue with that, than anything else and I would consider a Lauf fork, however I've read that it doesn't handle washboard too well.

Originally Posted by simplemindThanks for the writeup! How does it do on washboard? I have more of an issue with that, than anything else and I would consider a Lauf fork, however I've read that it doesn't handle washboard too well.

Good question. The Kinekt isn't a suspension, in that it does nothing to help the wheels stay in contact with the ground. While it does absorb the impact of washboard on your backside, it does nothing to help your bike's handling on washboard, and the concussive impact on your hands, arms, and upper body. What I notice when I hit some washboard on high speed descents, is that while my bike is vibrating and transmitting a lot of noise to my hands and arms, my butt is quiet and stable. This is true as well for similar encounters with chunky gravel. If your concern is loss of traction and control on washboard, then this isn't a solution. As far as impact on your body, the Kinekt does literally save your butt; but the rest of you will get a good shaking.

Originally Posted by chasI own Canyon VCLS, Specialized CG-R, and Thudbuster (ST). I can't imagine doing long gravel without something to take the harshness out of the bumps. Body Float looks like a top shelf offering.

I didn't comment on the Thudbuster, which I also own. While the Thudbuster is the same idea, I find that it's elastomer system doesn't work nearly as well as the Kinekt dual steel springs; and lacks the easy adjustability of the Kinekt's spring/pre-load system.

Good question. The Kinekt isn't a suspension, in that it does nothing to help the wheels stay in contact with the ground. While it does absorb the impact of washboard on your backside, it does nothing to help your bike's handling on washboard, and the concussive impact on your hands, arms, and upper body. What I notice when I hit some washboard on high speed descents, is that while my bike is vibrating and transmitting a lot of noise to my hands and arms, my butt is quiet and stable. This is true as well for similar encounters with chunky gravel. If your concern is loss of traction and control on washboard, then this isn't a solution. As far as impact on your body, the Kinekt does literally save your butt; but the rest of you will get a good shaking.

Yes, I know it's not a suspension other than suspending your backside, and I wasn't thinking that it would have any effect on the bikes performance. What I was wondering is if you had experienced any boing-boing or pogo type reaction in a washboard situation. Just did a 66 mile race with about 40% washboard and by the time I finished EVERYTHING hurt, so I'm looking for a better solution than a solid carbon seatpost and fork. I'd like to hear from some front shock people (Lauf/Lefty/Fox) and their washboard experience...which offers the most bang for buck, seat or fork?Thanks for the info!

Yes, I know it's not a suspension other than suspending your backside, and I wasn't thinking that it would have any effect on the bikes performance. What I was wondering is if you had experienced any boing-boing or pogo type reaction in a washboard situation. Just did a 66 mile race with about 40% washboard and by the time I finished EVERYTHING hurt, so I'm looking for a better solution than a solid carbon seatpost and fork. I'd like to hear from some front shock people (Lauf/Lefty/Fox) and their washboard experience...which offers the most bang for buck, seat or fork?Thanks for the info!

To be honest, I'm not sure. I haven't tackled anything that demanding on my rides with the Kinekt. Kinekt claims a 60% reduction in concussive impact from your saddle. I have no way to confirm that claim. My experience with washboard, is that for short stretches, the Kinekt does give you significant back end relief. The rest of your body however, especially your wrists and arms, take a beating. For the type of race you describe, I think you would want a drop bar fully suspended mountain bike or monster cross. While a shock post like the Kinekt would be far less expensive than a true suspension, IMHO, it wont solve your problem. There really isn't a cost benefit comparison. I don't think that the Kinekt can do the job. Hope this helps.

I saw an interesting video that bluntly stated that bigger tires were better than front suspension – the route was paris Roubaix and the big tires were the 650/47 WTB vs Lauf Grit. Food for thought (on cobbles at least).

I find some benefit from a suspension seat post in that it allows me to stay seated and the tire planted over washboard vs having to stand and hope my legs can absorb the washboard.

I saw an interesting video that bluntly stated that bigger tires were better than front suspension – the route was paris Roubaix and the big tires were the 650/47 WTB vs Lauf Grit. Food for thought (on cobbles at least).

I find some benefit from a suspension seat post in that it allows me to stay seated and the tire planted over washboard vs having to stand and hope my legs can absorb the washboard.

Good point about staying seated with a suspension post. Not only on washboard, but when descending and climbing as well. I find that I'm more comfortable keeping weight on the saddle. which helps me maintain control - especially while cornering and keeping weight on the outside pedal. BTW, I raced in Belgium on cobbles as a 19 year amateur in 1962. Some of the cobble stone roads we raced on were built by the Roman Army. I would say, from memory, some of the washboard I ride are comparable. But when the coble's were wet, they were greasy as snot. Virtually unrideable. Typically, everyone would sprint for the dirt paths that lined the road. Our tires were Clement tubulars with natural latex tubes. We didn't own a floor pump. We had to pump our tires daily with Silca frame pumps. I doubt that we ever ran these tires at over 70 PSI. Probably much less. Surprisingly few punctures. I never had one in a race.

I saw an interesting video that bluntly stated that bigger tires were better than front suspension – the route was paris Roubaix and the big tires were the 650/47 WTB vs Lauf Grit. Food for thought (on cobbles at least).

I find some benefit from a suspension seat post in that it allows me to stay seated and the tire planted over washboard vs having to stand and hope my legs can absorb the washboard.

I need to see that video! I remember watching some slo-mo video of bodies in the Paris-Roubaix and it was wild, even with their ultra thin bodies, you could see the muscles and skin flailing with the mini impacts of the cobbles.

Quote:

Originally Posted by bobknh

Good point about staying seated with a suspension post. Not only on washboard, but when descending and climbing as well. I find that I'm more comfortable keeping weight on the saddle. which helps me maintain control - especially while cornering and keeping weight on the outside pedal.

I need to see that video! I remember watching some slo-mo video of bodies in the Paris-Roubaix and it was wild, even with their ultra thin bodies, you could see the muscles and skin flailing with the mini impacts of the cobbles.

Interestingly I did a test on some harsh washboard yesterday with some 32mm tires on my Inflite with a canyon seat post

At 15-16mph the canyon carbon seat post just soaked up the harshest washboard. I didn't realize how hard I was punishing it until I put my weight forward gripped the handlebars - the front of the bike was getting the cr*p violently beat out of it. I quickly put my weight back on my saddle with a light touch on the bars.

I don't know how much was the bike and how much was the seat post, but dang, the back of this setup soaks up bumps. I do think that at speeds closer to 20mph+ that the bike would just violently skip across the tops of the crest of the washboard, but I haven't had a need to use the thudbuster since getting this bike/seatpost combination.

Originally Posted by chasInterestingly I did a test on some harsh washboard yesterday with some 32mm tires on my Inflite with a canyon seat post

At 15-16mph the canyon carbon seat post just soaked up the harshest washboard. I didn't realize how hard I was punishing it until I put my weight forward gripped the handlebars - the front of the bike was getting the cr*p violently beat out of it. I quickly put my weight back on my saddle with a light touch on the bars.

I don't know how much was the bike and how much was the seat post, but dang, the back of this setup soaks up bumps. I do think that at speeds closer to 20mph+ that the bike would just violently skip across the tops of the crest of the washboard, but I haven't had a need to use the thudbuster since getting this bike/seatpost combination.

Thanks for info. on the Canyon, which I believe is a re-branded model from another German manufacturer. The Canyon 2 leaf design is lighter than the Kinekt, and scores higher in ascetics. I was tempted to try it. Which model are you using? I saw 3 models available on the Canyon EU website; but it wasn't listed on the Canyon US site. Where did you buy yours? The main advantage of the Kinekt though is that you can easily tune the suspension by increasing or decreasing the spring load with the external 4mm spring load screw. Spmething you can't do with the Canyon, or easily on the Thudbuster. Markings on post show you your exact pre-load setting, so that you van easily return to any setting for any conditions. I find that riding on pavement I can set the pre-load around the "3" mark, but drop it back to "2" for dirt and gravel. You can change the pre-load in a few seconds off the bike with a 4mm allan key. Or, if you buy the optional key load thumb screw, you don't even need the 4 mm allan.

Mine came on the bike (Canyon Inflite). It is the normal looking one. Ergon sells the two bladed one Canyon uses.

I was surprised to read that they both blew away the competition (passive carbon post) in a test, and was skeptical. I had planned on taking it off the bike and using the Specialized CG-R. But after riding both, well the test was right. The Canyon/Ergon ones are a lot better.

A thudbuster (or by extension the better Kinekt Body Float) are in a different category, being active. They feel like adding an extra 1" to tire volume (or cutting tire pressure down by 50%). But, the canyon one (on the Inflite at least) does all I need.

One caveat - the flexy carbon posts need a lot of post showing to work. I put one the CG-R on a bike at the minimum insertion depth (horizontal top tube), and it didn't do squat. A thudbuster or body float is much superior in this situation.

Originally Posted by chasMine came on the bike (Canyon Inflite). It is the normal looking one. Ergon sells the two bladed one Canyon uses.

I was surprised to read that they both blew away the competition (passive carbon post) in a test, and was skeptical. I had planned on taking it off the bike and using the Specialized CG-R. But after riding both, well the test was right. The Canyon/Ergon ones are a lot better.

A thudbuster (or by extension the better Kinekt Body Float) are in a different category, being active. They feel like adding an extra 1" to tire volume (or cutting tire pressure down by 50%). But, the canyon one (on the Inflite at least) does all I need.

One caveat - the flexy carbon posts need a lot of post showing to work. I put one the CG-R on a bike at the minimum insertion depth (horizontal top tube), and it didn't do squat. A thudbuster or body float is much superior in this situation.

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